MARINE AQUARIA 



temperate and tropical genera. Those of the Atlantic and Pacific oceans 

 are similar, but for the purpose of this volume the Middle Atlantic coast 

 species only will be described. 



Cape Cod is accepted as the dividing line, as north and south of it a 

 markedly different marine flora exists, because the great arctic and equa- 

 torial currents maintain diflPerent temperatures of the water; and though 

 the more common seaweeds may be found in both sections, those to the 

 north are essentially arctic and those to the south temperate zone species. 

 About a third of the species of each section do not extend very far into 

 the other. The common forms here mentioned occur from New England 

 to the Carolinas and some still further south. 



Green Marine Alg^. Chlorospermeae have the widest range, 

 and those tide-mark forms which flourish in full light and where freshwater 

 reaches them at some stages of the tide, or which survive when laid bare 

 by the receding tides, are the hardiest and will thrive best in the marine 

 aquarium. Of these Green Algas the most generally distributed species 

 are: 



Ulva lactuca, (Linn.) or Sea Lettuce, Oyster Green, has pale yellow- 

 ish-green 6 to 8 inches long and 4 inches wide, thin, membranous fronds 

 with crisped edges, which consist of a single layer of cellules. Quite 

 generally distributed on the Atlantic coast between tide-marks and in 

 deeper water, usually attached to all kinds of objects in the water, 



Ulva lattssma{I-,mn.) or Green Laver, Heavy Sea Lettuce, has dark 

 bluish-green very much broader variable fronds, which may attain a length 

 of 24 to 36 inches and a width of 12 to 20 inches. The fronds are thin, 

 soft and glossy, of irregular outline with waved and ragged edges. It 

 grows attached below low-tide marks and is common everywhere. 



Purpyra vulgaris (Ag.) or Purple Laver, Purple Weed, is variable in 

 color and may have blackish-green, purple or brown, with thin, satiny, 

 ribbon-like fronds, elegantly waved, crisped and puckered on the edges. 

 The fronds are also variable in form, sometimes two inches broad in the 

 centre and tapering to both ends, or a broad membrane ten inches across. 

 Common in shallower water everywhere, but grows to largest size in Cali- 

 fornia. 



Enteromorpha intestinalis (Link.) or Gut Weed, has simple unbranched 

 fronds 6 to 10 inches high and ^ inch wide, slender at the bottom but 

 of the same width above. It is often inflated with air bubbles and then 

 assumes the intestinal appearance indicated by the name. The color is 

 light green, often yellow or white at the top. Grows in tide-pools and 

 shallow water along the Middle Atlantic coast. 



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